Advantages of XERUN-120A-V3.1 speedo★ Aluminum bottom case improves the heat dissipation (The previous V3 speedo uses plastic bottom case);★ Improved heat-sink with 1mm gap between the cooling fan allows more air flow to reduce the temperature of speedo;★ Improved dust-proof design. Rubber rings are applied at the sensor port and the program port;★ Aluminum screws of cooling fan look better and more professional;★ Improved electronic switch has stronger current endurance to be more reliable;★ New firmware allows driver to adjust the throttle neutral range, and solves the "turbo lost in high temperature" problem in the previous version firmware.